Re: [PATCH v4 1/1] build: add libarchive to external deps

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Nov 03, 2023 at 09:38:53AM -0700, Srikanth Yalavarthi wrote:
> In order to avoid linking with Libs.private, libarchive
> is not added to ext_deps during the meson setup stage.
> 
> Since libarchive is not added to ext_deps, cross-compilation
> or native compilation with libarchive installed in non-standard
> location fails with errors related to "cannot find -larchive"
> or "archive.h: No such file or directory". In order to fix the
> build failures, user is required to define the 'c_args' and
> 'c_link_args' with '-I<includedir>' and '-L<libdir>'.
> 
> This patch adds libarchive to ext_deps and further would not
> require setting c_args and c_link_args externally.
> 
> Fixes: 40edb9c0d36b ("eal: handle compressed firmware")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Srikanth Yalavarthi <syalavarthi@marvell.com>

I think this is the cleanest solution to the problem you were having.

Acked-by: Bruce Richardson <bruce.richardson@intel.com>

One minor comment below. Patch is ok without taking it on board if you
like.

> ---
> v4:
>   - Rebase over latest main
> v3:
>   - Add to libarchive ext_deps
> v2:
>   - Update ml/cnxk meson config
> v1:
>   - Initial patch
> 
>  config/meson.build          | 5 -----
>  drivers/ml/cnxk/meson.build | 1 +
>  lib/eal/meson.build         | 3 +++
>  3 files changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/config/meson.build b/config/meson.build
> index 0968351740..250833d0a4 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -241,11 +241,6 @@ dpdk_conf.set('RTE_BACKTRACE', cc.has_header('execinfo.h') or is_windows)
>  libarchive = dependency('libarchive', required: false, method: 'pkg-config')
>  if libarchive.found()
>      dpdk_conf.set('RTE_HAS_LIBARCHIVE', 1)
> -    # Push libarchive link dependency at the project level to support
> -    # statically linking dpdk apps. Details at:
> -    # https://inbox.dpdk.org/dev/20210605004024.660267a1@sovereign/
> -    add_project_link_arguments('-larchive', language: 'c')
> -    dpdk_extra_ldflags += '-larchive'
>  endif
>  
>  # check for libbsd
> diff --git a/drivers/ml/cnxk/meson.build b/drivers/ml/cnxk/meson.build
> index 0680a0faa5..921dc7e89b 100644
> --- a/drivers/ml/cnxk/meson.build
> +++ b/drivers/ml/cnxk/meson.build
> @@ -67,6 +67,7 @@ sources += files(
>          'mvtvm_ml_model.c',
>  )
>  
> +ext_deps += libarchive

minor nit - I don't think this is necessary. If libarchive is found, then
DPDK eal will be linked against it, and so all other drivers should simply
have that as a transitive dependency.

Same probably applies to jansson.

>  ext_deps += jansson_dep
>  ext_deps += dlpack_dep
>  ext_deps += dmlc_dep
> diff --git a/lib/eal/meson.build b/lib/eal/meson.build
> index 9942104386..e1d6c4cf17 100644
> --- a/lib/eal/meson.build
> +++ b/lib/eal/meson.build
> @@ -21,6 +21,9 @@ endif
>  if dpdk_conf.has('RTE_USE_LIBBSD')
>      ext_deps += libbsd
>  endif
> +if dpdk_conf.has('RTE_HAS_LIBARCHIVE')
> +    ext_deps += libarchive
> +endif
>  if cc.has_function('getentropy', prefix : '#include <unistd.h>')
>      cflags += '-DRTE_LIBEAL_USE_GETENTROPY'
>  endif
> -- 
> 2.42.0
>